The present invention relates to an MRAM module configuration containing a multiplicity of memory cell zones, which each contain a memory array having a multiplicity of memory cells and peripheral circuits surrounding the memory array on the sides of the latter. The peripheral circuits surround the memory array in such a way that, in a plan view, each memory cell zone has an essentially cruciform structure.
In magnetoresistive random access memories (MRAMs), as is known, the memory effect resides in a magnetically variable electrical resistance of a memory cell. The MRAM memory cell is disposed between a word line and a bit line, which crosses the word line essentially perpendicularly and at a distance. At the crossover point between the word line and the bit line, there is a multilayer system containing a fixed or hard magnetic layer and a free or soft magnetic layer and also a tunneling barrier layer situated between these layers. The hard magnetic layer, the tunneling barrier layer and the soft magnetic layer form a magnetic tunnel junction (MTJ) cell.
It is accordingly an object of the invention to provide a MRAM module configuration that overcomes the above-mentioned disadvantages of the prior art devices of this general type, in which the highest possible packing density of memory cell zones is achieved with utilization of free corner areas.
With the foregoing and other objects in view there is provided, in accordance with the invention, a magnetoresistive random access memory (MRAM) module configuration including a multiplicity of memory cell zones each containing a memory array having a multiplicity of memory cells and peripheral circuits surrounding sides of the memory array. The peripheral circuits surround the memory array in such a way that, in a plan view, each of the memory cell zones have a substantially cruciform structure. The memory cell zones are nested in one another in such a way that, in individual rows, the memory cell zones are offset with respect to one another.
In the case of an MRAM module configuration of the type mentioned in the introduction, the object is achieved according to the invention by virtue of the fact that the memory cell zones are nested in one another in such a way that a high packing density of the module configuration is present with utilization of free corner areas of the cruciform structure.
The cruciform memory cell zones are thus configured in such a way that they can be nested in one another. A significantly increased packing density is achieved as a result. This holds true even when no ideal cruciform structures are present, rather each memory cell zone has a free area in at least one corner.
In accordance with an added feature of the invention, the peripheral circuits of one row of the memory cell zones project into free corner areas of the memory cell zones of adjacent rows.
In accordance with an additional feature of the invention, the peripheral circuits have a substantially rectangularly shaped structure.
In accordance with another feature of the invention, the memory arrays are substantially square shaped or rectangularly shaped.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a MRAM module configuration, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.